Update README.md

Author: EliteMasterEric

README.md

@@ -3,8 +3,9 @@
 ## Table of Contents
 
 1. [Fundamentals](https://github.com/FunkinCrew/funkin-modding-docs/blob/main/01%20-%20Fundamentals.md)
-2. [Custom Songs and Custom Levels](https://github.com/FunkinCrew/funkin-modding-docs/blob/main/02%20-%20Custom%20Songs%20and%20Custom%20Levels.md)
+2. [Custom Songs and Custom Story Levels](https://github.com/FunkinCrew/funkin-modding-docs/blob/main/02%20-%20Custom%20Songs%20and%20Custom%20Levels.md)
 3. [Custom Characters](https://github.com/FunkinCrew/funkin-modding-docs/blob/main/03%20-%20Custom%20Characters.md)
+4. [Custom Stages](https://github.com/FunkinCrew/funkin-modding-docs/blob/main/04%20-%20Custom%20Stages.md)
 10. [Appending and Merging Files](https://github.com/FunkinCrew/funkin-modding-docs/blob/main/10%20-%20Appending%20and%20Merging%20Files.md)
 
 ## Contributions